# Cosmological Tests of Gravity

## TL;DR

This review discusses how cosmological observations can test and constrain modifications to General Relativity, focusing on large-scale structure, gravitational screening, and future survey prospects.

## Contribution

It provides a unified framework for describing extended gravity theories and their effects on cosmic structure formation and observational constraints.

## Key findings

- Current large-scale structure constraints limit modified gravity models.
- Gravitational screening mechanisms can hide deviations from General Relativity.
- Future surveys will significantly improve tests of gravity on cosmological scales.

## Abstract

Cosmological observations are beginning to reach a level of precision that allow us to test some of the most fundamental assumptions in our working model of the Universe. One such an assumption is that gravity is governed by the General Theory of Relativity. In this review we discuss how one might go about extending General Relativity and how such extensions can be described in a unified way on large scales. This allows us to describe the impact of modified gravity on the growth and morphology of the large scale structure of the Universe. On smaller scales we explore the physics of gravitational screening and how it might manifest itself in galaxies, clusters and, more generally, in the cosmic web. We then analyze the current constraints from large scale structure and conclude by discussing the future prospects of the field in light of the plethora of surveys currently being planned.